Subject: A static recording of a tennis ball placed on a table. Narration:As noon approaches, it grows increasingly confused, as the creatures around it show no sign of using it for its intended purpose. Struggling to attract their attention, it becomes ever more distressed as it finds itself completely immobile.
It may also be psychic (or at least very observant):
Subject: An incidental recording of Dr. ██████ made by Dr. ████████ during unrelated experimentation. Narration:Despite the male's calm facade, his lust for his female companion is extraordinary. The degree to which his obsession reaches has become nearly unhealthy, dominating his thoughts at every turn. Wild fantasies course through his mind when he watches her when she doesn't notice. Researcher Note: Dr. ██████ was treated for a broken nose after being attacked by Dr. ████████ and both researchers have been placed on administrative leave for a period of no less than two (2) weeks pending disciplinary action and transfer to another site.
Necessarily Evil: The SCP Foundation recognizes that it does very bad things, for the greater good of humanity.
The "Unfounded" mini-canon is built on the premise that this is not true, taking place in a universe where there is no Foundation, and yet things are still pretty much the same, with other Groups of Interest taking up the slack.
Never Heard That One Before: SCP-294 can take any liquid (or anything that can become a liquid) within its unknown range and pour it into a plastic cup. One request was so common that it lead to a special note:
** Addendum [SCP-294ad]: ** In order to stem the daily tide of attempts, it is now officially noted that keying in "two girls" gives the standard "OUT OF RANGE" error message. Come up with something more original next time.
Nice Job Breaking It, Hero: A number of SCPs were either benign or dormant until the Foundation got their hands on them. It's only after some ill-conceived test is performed on it that it begins to become "uncooperative". And, when you're containing a minor deity, you do NOT want to make him uncooperative.
A particularly memorable one is SCP-1322. It's a portal to an alternate dimension. The inhabitants were friendly at first, until the Foundation offered to help them synthesize a vaccine to a viral epidemic on their side. Turns out the vaccine also acted as a Depopulation Bomb. They are pissed.
SCP-1777: Researchers accidentally kill a man who was given a weapon by an SCP. Nice job killing King Arthur's heir.
SCP-687: A test subject used it to escape through time and become The Cleveland Torso Killer and Black Dahlia Murderer.
SCP-1970: Just an old TV that used tiny glowing humanoids for pixels until researchers opened the glass and accidentally killed them.
Each new item has, without fail, had a negative effect on the house’s inhabitants. SCP-1122-1 [dad] has frequently been seen drinking, lamenting how "things should be better," while SCP-1122-3 [daughter] and SCP-1122-4 [son] have become more introverted and are rarely seen outside their rooms.
The potential for this to occur due to gratuitous usage of Class-Ds (which, let's face it, is most of the time) is brought up on one talk page:
"It always bugs me when they send in the D-Class before the drones or lowered cameras or whatever. Good thing these dimensions always just contain a monster that eats D-Class personnel rather than, say, a button that makes the first person who presses it turn into a living God or something."
The Global Occult Coalition, which aims to destroy all anomalous items regardless of their actual threat, is all about this: They turned a helpful chair into a very defensive pile of splinters, and wiped out a village just because they were "infected" with harmless, "imaginary" (or were they?) flightless birds.
SCP-425: A television set which broadcast weird vision by itself on the 8th, 16th, and 24th day of each month, even when unplugged. It's harmless, but if you born on days of the month that are multiples of 8 (e.g. 8, 16, and 24), then the vison will include moving through a black hole, and experience "a crushing sense of oblivion". Then you will have recurring nightmares for weeks, and even extensive psychotherapy only reduced the nightmare to once a month.
30% of SCP-1881-B players report lasting psychological effects afterwards, in the form of nightmares related to its contents (and occasional visual/auditory hallucinations).
90% of Your Brain : SCP-1475 can use 100% of his brain because he needs to regulate everything his body would normally do automatically. The author wrote this specifically because they hated the "__% of your brain" trope.
Any time experiments are cancelled on SCPs that violate common sense or would possibly replicate something nasty.
No Name Given: The O5. Most of the time, even their identification numbers are blanked out. Often, researchers have their blanked out. D-Class, being expendable, don't have names, just numerical designations.
Averted with O5-12, the father of SCP 321, whose first name is Adam in a nod to the long tradition of meaningful names and nods towards The Bible in the Foundationnote Assume that O5s are still normal humans, Adam was in the Federation since 18██, then the current O5-12 play this trope straight.
Non-Indicative Name: This tends to come up a lot when discussing the Foundation's means of categorizing SCPs, mainly because when a Foundation operative says an object is "safe", they mean "nothing will happen if it's left alone in a locked room". A hydrogen bomb is "safe" by those standards.
Noodle Implements: Some of the SCP objects become this, when SCP numbers are listed in incident reports or other articles; occasionally the SCP with that designation will appear completely irrelevant to the context in which it was referenced.
That's often due to the original SCP being removed, and a new one filed under that number.
Also, the FAQ's tongue-in-cheek explanation of what Procedure 110-Montauk is consists of a bunch of [DATA REDACTED]s interspersed with mentions of an elephant, a bed of live cobras, Barbara Streisand's Greatest Hits, something that is over seventeen feet long, a staple remover, a feather boa that absolutely must be black (and not dark blue), and "plutonium splitting the atom."
Updated to "An amateur shadowcast of the Rocky Horror Picture Show."
Noodle Incident: Every single time you see "[DATA EXPUNGED]" or "[REDACTED]"; it seems like the whole idea is to have at least one such incident per SCP. The unspecified reason why SCP-447 must never come into contact with dead bodies is especially noodly and is occasionally referred to elsewhere (as seen below, it scares O5-2 shitless).
The first thumbnail in SCP-1231 is redacted, which is odd, considering that whatever you think the thumbnail contains is then created as a new thumbnail, and that the thousands of other thumbnails all derived from the first perception of the original.
No OSHA Compliance: Played straight, subverted and averted in different sections of the site. In the SCP articles themselves, the containment procedures are designed to minimize danger, risk, and loss of life, even of the utterly expendable D-Class. In the testing logs, the prison-recruited D-class personnel are regularly treated to definitely unethical and probably lethal experimentation, often in cases where little useful information is likely to result, and are often subjected to the machinations of some of the more diabolical SCPs purely for the amusement of the ranking research staff. Finally, anyone who works at the Foundation willingly is expected to follow reasonable safety procedures, although considering the nature of some SCPs they still have a short life expectancy.
No Sell: Former SCP-151-D exhibited this along with other Marty Stu traits, shrugging off effects of other SCPs just because. His termination log consists much of the same, until he's finally destroyed... rather messily. invoked
No Sense of Direction: SCP-920, also known as Mr. Lost. Try to take him somewhere, or just walk with him for a while, and you will get lost. (However, apparently because all the super-deadly gets old if everything is super-deadly, the description has a notice that lost means "lost" as in "misplaced" and not some horrible fate. However, you can be lost to pretty much anywhere in the world.)
When they tried to contain him, a whole facility got lost. It remained where it was but nobody could ever find it, leading to its closure due to running out of supplies.
Not-So-Harmless Villain: Many of the SCPs. In particular is SCP-387, a set of sentient Legos. Ordinarily they're benign, and even kind of cute. But put a knockoff set of Legos nearby, and they will do something Redactable.
Nothing Is Scarier: The guidelines for writing new SCP reports encourage vagueness so that the reader fills in the horror for themselves, which is more effective than detailing something that may just fall flat.
Judging by the details of one uncensored article, everything behind those [DATA EXPUNGED] is worse than you think.
SCP-579. What is it? We don't know. Whatever it is, the SCP Administration felt it was so dangerous that even the description of it is gone. They even killed all the people working on it, save 7 agents that act as advisers in case it ever gets loose. It's so bad that it's currently stored in an alternate universe — after having destroyed at least 4 other containment sites, with a very specific containment procedure, and if it ever fails, even for a minute, policy is to destroy the alternate universe to contain it. And if that fails?
In the event of an unsuccessful Action 10-Israfil-B, no further action will be necessary. [DATA EXPUNGED]
Nuclear Option: Most (if not all) Sites have on-site nuclear warheads, to be detonated in the event of a breach by a Keter-class SCP or Site failure.
But they are actually afraid to try it on SCP-682 because it might not only survive, it could become even stronger.
Our Angels Are Different - Shockingly averted. The Foundation goes to extensive lengths to document the fact that Dr. Clef's proposal for SCP-001 is indeed a bona fide Judeao-Christian Angel without any major subversions. It does however play more to the descriptions in Holy texts as opposed to cultural depictions, for instance appearing to have as many as 108 wings and being made of fire.
Played Straight, though, with SCP-469. Disturbingly straight.
Panacea: SCP-500, pills that cure any disease, but there's just about fifty of them and they're impossible to replicate perfectly (though knockoffs can work if you're lucky). Later, SCP-427: the Lovecraftian Locket was developed that has eclipsed it in use, although with the possible side effect of mutating you into a squid.
Parody Sue: Several. Most notably, SCP-10101-j (a parody of overpowered wish-fulfillment self-inserts), SCP-777-j (a parody of god mode black hole sues), and SCP-496-j (a parody of Purity Sues, whose name actually references the original Mary Sue). SCP-316, later terminated with extreme enthusiasm by the resident Wonka, reads much like one but was apparently intended as a serious SCP.
Perpetual Motion Machine: So many SCPs (labeled ectoentropic) ignore the laws of thermodynamics, being able to produce infinite amounts of matter, energy, or their constant movements could be used as a power generation tool. Sadly, most are either too valuable or dangerous to use.
Person of Mass Destruction: Most of humans housed by the Foundation (and maybe the researchers), especially if their object class is Keter.
Pet the Dog - Most sentient SCPs are accomodated reasonably well, depending on their potential danger, ability to escape, and willingness to cause harm. The most (relatively) harmless are given furnished rooms and are generally given whatever they request, as long as it doesn't violate security. They are, of course, not allowed to leave the facility.
SCP-103 was the only SCP that the Foundation actually released. It says something about the Foundation's Well Intentioned Extremism that a man who's only power is that he never gets hungry is the only SCP ever let go without being terminated (and even that is, according to the comments, a controversial decision). He got retconned to having worms in his stomach that fly out and eat people and never having been released.
Admittedly, some of the SCPs are given the best care possible. Every effort is made not to upset the autistic girl, for example, and the harmless and friendly living eyeballs have free run of their site. And one of the first tests of the vending machine was "something Cassy will like," Cassy being a mentally normal young woman who exists in 2-D.
Several SCPs which fall into a self contained microcosm, pocket universe, etc, or other SCPs that were created by the Foundation on accident, respect or outright revere the Foundation. On the other hand, some fall into a Rage Against the Heavens.
Some SCPs that are relatively harmless are just glad to have someone talking to / using them again, in many cases having been abandoned for years after their original owner died.
Power Perversion Potential - SCP-294 is a vending machine that can produce twelve ounces of just about anything as long as it's liquid. A security guard started using it to produce and sell heroin and meth before being caught.
Primal Fear: Many of SCP-1881's stage iterations invoke these, such as a level appearing to be upside-down without gravity being reversed to match, a shmup stage with no enemies (leaving the player floating aimlessly through empty space for several minutes before the level ended), and being trapped in a maze with an increasingly large number of deadly creatures.
Produce Pelting - SCP-504 is a breed of tomato that throws itself if someone cracks a bad joke. If the joke is bad enough, it will break the sound barrier.
Item: Three mature SCP-504 tomatoes, one for each test subject. Subject: After the introduction to the following news item, "Bomb blows hole in Lenin statue", the three following jokes were made. Test Subject 1: Ooh, that's gonna leave a Marx. Result: Tomato number one 'twitched', but did not displace from its original location. Test Subject 2: BBC is just Stalin the good news. Result: Tomato clocked at 152 mph. Chipped tooth and hairline jaw fracture. Test Subject 3: That blows. Result: Tomato clocked at [REDACTED]. Subject is hospitalized with a massive skull fracture.
And when shown a recent episode of Saturday Night Live, high-speed photography showed that the tomato changed velocity several times (including a brief jump backward), as if unable to decide whether the sketch was genuinely lame or just "bad" in an ironicsense.
Reality Retcon: The "Big Bloop, a Real Life unexplained extremely-loud underwater sound, was caused by SCP-169, an enormous undersea creature which is at least 1,000 km in length. The Foundation had a spy in the National Oceanic and Atmospheric Administration who tried to prevent the public from learning of the Bloop, but failed.
Reality Writing Book: SCP-140 is a very specific version; the book writes itself and alters reality as a consequence, given a suitable form of ink or ink substitute. SCP-687 is a text adventure video game with broader abilities.
Red Shirts: The Class D's, of course. Lampshaded: Dr. Bright cannot change the standard issue D-Class uniform to black pants with a red polo shirt.
Replacement Goldfish: SCP-1976 was made by a man to be this for his family after he died of a brain tumor. He thought its powers would make his family see it as their husband and father, instead it caused his wife to think it was her father while his children weren't old enough for its powers to work. It currently causes anyone within its activation criteria who looks at it to think its their father while their real father becomes a stranger.
Research Inc: the Foundation benefits commercially form their research.
Retcon: The Mass Edit, which was basically the wiki admins purging some of the more dubious entries and retconning out some of the more ludicrous (and humorous) aspects of the backstory. (See below.)
Ret Gone: When Fishmonger (the writer) was banned, he demanded to have all of his characters and stories to be removed from the SCP Wiki. Some of his more famous characters were referenced in many articles. This left many gaps.
And before that, all of the SCPs deleted during the Mass Edit.
To make things even more confusing, since the numbers for Ret Gone SCPs were freed up, the wiki wound up with new SCPs under old numbers.
On a not so funny note, that may be to KEEP you from gagging.
DO NOT allow SCP-447-2 to come into contact with dead bodies!
It eventually gets to the point that all of the researchers mention their fear of it coming into contact with dead bodies in the most unlikely of circumstances (such as dead bodies drinking milk).
And other forces seem to play on that fear, such as when SCP-914 transforms a dead body into SCP-447-2.
The real reason for this fear is that Doctor Alistair is very afraid of dead bodies and he's the one in charge. So he made up crap to get away with it and it took a life of it's own.
One story actually DOES describe some of the adverse effects of SCP-447 touching a dead body. In the aftermath, a dimensional rift opened up and dragged Dr. Clef into an alternate reality.
SCP-447 also seems to have an obsession with the color green and the smell of mint. Applied to the cure-anything-pill, SCP-500, the pill still cures anything, but leaves the subject with "minty-fresh breath". Applied to a subject's eyes, it improves that person's vision significantly, with the side effect of tinting that person's vision green, including coloring the eyes themselves green. It can also: harden concrete, make milk lactose-free (and give it a slight minty taste), decontaminate water to a limited degree (as well as tinting it green), and increase a car's functioning significantly (windshield wiper fluid will literally repel dirt and grime, radiator fluid will double the temperature needed to overheat the engine, and mixed into gasoline will increase fuel efficiency by 150%).
There's also how the discovery of any SCP being potentially lethal inevitably leads to someone wondering if it could be used to kill SCP-682.
And any object that produces or transforms other objects (ala the vending machine and 914) will inevitably produce something shaped like SCP-682.
Dr. King and his apple seeds.
That the common typo of SCP, SPC, is an Alternate Universe version of the Foundation, the Shark Punching Center.
Some articles have either addendums or notes warning personnel to stop using them for pranks, party games, or as quick hangover remedies. This is being phased out and frowned upon, as a majority of the senior members now find it unfunny, trite, and unprofessional.
Also "demoted to Keter-duty", it's also unprofessional, and would you want people who broke rules or screwed up a lot being assigned to the most dangerous items? Unlike funny addendum, this gag serve the purpose of indicate how serious the Noodle Incident is (like, has 447 come into contact with dead bodies), rather than being the result of silly personal. So it still remain in old SCPs, and still accepable to use when making reference to those old article.